1. Field of Invention
This invention relates to an artificial dental implant.
2. Description of the Prior Art
There are known artificial dental implants which can be used in place of the roots of natural teeth. An artificial dental implant is constructed with an implanted part (fixture) which is to be implanted in the bone tissue and a crown-fixing part (abutment screw) to which a crown is to be fixed.
As for materials for forming such artificial dental implants, (1) metals such as stainless steel and Ti (titanium) and the like, and (2) ceramics such as zirconia-based, alumina-based and sapphire-based ceramics are conventionally used.
However, artificial dental implants formed from ceramics have the disadvantage of low strengths, and therefore they are likely to be easily damaged. Moreover, ceramic artificial dental implants are very expensive.
Consequently, attention has focused on metal artificial dental implants with which there are fewer disadvantages described above. Such metal artificial dental implants are usually made by means of casting and a machining process performed after the casting process.
Among the metal artificial dental implants, stainless steel artificial dental implants have poor bio-compatibility, so that they have adverse effects on the body such as causing the onset of metal allergy and the risk of cancer resulting from the dissolution of Ni and Cr.
On the other hand titanium (Ti) artificial dental implants are relatively light and have high strength, and they have excellent corrosion resistance and bio-compatibility.
However, in the case of Ti artificial dental implants, cutting processes using special tools and laser working must be carried out on the castings or ultra-plastic mold processing is required, to manufacture and process them, thus resulting in a problem in that production is not easy. In particular, a complicated manufacturing process and a high degree of skill are required to process the castings into complicated and fine shapes, so that the manufacturing costs are also increased.
Further, the bio-compatibility of Ti itself is not so excellent. Consequently, in Ti artificial dental implants, there is a case that a long time is required after they are implanted in the patient's bone tissue until they become fixed with the bone tissue. Accordingly, depending on the particular case, there is a case that the artificial dental implant which has been implanted in the bone tissue is fall out.